Until blood products are fully evaluated and found to be acceptable for release to a transfusing facility or patient, they must be kept separate from other products that have already been through the testing process and made available. Quarantine refers to that separation, and it can be both physical (storage in separate portions of a laboratory) and virtual (the blood establishment computer system, or “BECS” does not allow a label to be issued for the product until all checks and tests are complete and acceptable). Quarantine is also used when a previously acceptable product becomes questionable due to a variety of factors, including new post-donation information about the donor of the unit, a test result on a subsequent unit, etc. The principle is the same: Keep the product separate so that it can’t be issued in error.